Suppose $A$ and $B$ each roll a fair six sided dice $101$, $100$ times respectively. If we count the number of odds and evens in each sequence, what is the probability that $A$ has more number of odds than $B$ does?
I think the probability is $1/2$ if we roll both $A$ and $B$ the same number of times. But how does the probability change if we roll $A$ one more time?